﴿ فَلَمَّا رَجَعُوٓا۟ إِلَىٰٓ أَبِيهِمْ قَالُوا۟ يَٰٓأَبَانَا مُنِعَ مِنَّا ٱلْكَيْلُ فَأَرْسِلْ مَعَنَآ أَخَانَا نَكْتَلْ وَإِنَّا لَهُۥ لَحَٰفِظُونَ ﴾

“And so, when they returned to their father, [Joseph's brothers] said: "O our father! All grain is [to be] withheld from us [in the future unless we bring Benjamin with us]: send, therefore, our brother with us, so that we may obtain our measure (of grain]; and, verily, we shall guard him well!"”

Please check ayah 12:64 for complete tafsir.